Measure
• Auto-outline the inner part of the fiber
• Measure inner area and inner perimeter (a1 and p1)
• Find the border
• Auto-outline the outer part of the fiber
• Measure total area and outer perimeter (a2 and p2)

- Methods used for G factor calculation:

Two values are computed:

pgfactor, which is the perimeter-based g factor, is calculated this way:

pgfactor =

agfactor, which is the area-based g factor, is calculated this way:

agfactor =

pgfactor and agfactor are totally equal for an ideal round fiber. The more the fiber is distorted, the more these values will differ. If you should use only one of these values, the agfactor should be chosen because it is shape independent.